S. Korea detects quake near N. Korea's nuclear test site

A 2.7 magnitude earthquake was detected near North Korea's nuclear test site, South Korea's weather agency said, amid concerns about radioactive contamination following the North's powerful test in September.

The tremor occurred at 1:41 am (1641 GMT) on Friday, some 54 kilometers northwest of the Punggye-ri site where the North conducted its sixth and most powerful nuclear test on September 3, according to the Korea Meteorological Administration.

The natural quake occurred as the September 3 test weakened the grounds around the test site, the agency said. So far four aftershocks that followed the test have been reported, including two on September 23. The quakes have raised concerns in Northeast Asia about a possible radiation leak, but Pyongyang has claimed no radioactivity was released from the test site.